Exceptional Sequences, Braid Groups and Clusters
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چکیده
Introduction 1 1. Topological AR-quivers 2 2. Theorem of Brady-Watt and Bessis 3 3. Exceptional sequences 4 3.1. Basic definitions 5 3.2. Braid action on exceptional sequences 6 3.3. Example: Auslander-Reiten translation 7 4. Theorems about exceptional sequences 8 5. Appendix 10 5.1. Example: A2 10 5.2. More general almost split sequences 11 5.3. Bimodule of injectives 11 5.4. Untwisting in separable case 12 5.5. Inseparable case 13 References 14
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تاریخ انتشار 2009